This is an interdisciplinary proposal involving 6 departments (biochemistry, botany, crop science, entomology, genetics, and statistics) which is primarily devoted toward the determination of cellular and subcellular events associated with pesticide toxicity. A major effort is directed to elucidation of metabolic pathways involving oxidative and transferase enzymes. These studies include enzyme purification, enzyme reconstitution, and structure-activity relationships. Also included will be cooperative studies (Duke Univ.) involving the neuropathological action of EPN isomers. A closely related project involves studies on dermal and oral absorption of pesticides and the role of blood proteins in their further distribution. Purification of cholinesterases from a number of animal sources will continue, and a study of the biochemical differences among these enzymes is underway. In studies on the mode of action of herbicides, attention is directed to the manner whereby membrane fluidity and permeabilty is altered. Ultrastructural examination is used for confirmation. Genetic studies using Habrabrocon and Artemia as model systems are undertaken to examine possible adverse effects of toxicants on reproduction.